We look at the division of 413001 by 91 
The aim is to understand the frequency of 91 in 413001.

On to step 1:
4 divided by 91 is 0 with a remainder of 4.
Put 0 as the next digit of the answer. 
Result so far: 0.0
The remainder is 4 after subtracting 0 from 4.
Append the next digit (1) from the dividend to 4 and continue with: 41 / 91

On to step 2:
91 goes into 41 0 times with a remainder of 41.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 41 leaves us with 41.
Take the next digit (3) from the dividend and append it to 41, then repeat: 413 / 91

On to step 3:
91 goes into 413 4 times with a remainder of 49.
Write down 4 as next digit of the result. 
Result so far: 4.0
If we take 364 away from 413, we end up with 49.
Take the next digit (0) from the dividend and append it to 49, then repeat: 490 / 91

On to step 4:
When dividing 490 by 91, we get 5 with a remainder of 35.
Write down 5 as next digit of the result. 
Result so far: 45.0
Deduct 455 from 490 and we're left with 35.
Bring next digit (0) of the dividend behind the 35 and repeat the process: 350 / 91

Step 5:
When dividing 350 by 91, we get 3 with a remainder of 77.
Write down 3 as next digit of the result. 
Result so far: 453.0
The remainder is 77 after subtracting 273 from 350.
Include the next digit (1) from the dividend after 77, then repeat: 771 / 91

Moving on to step 6:
The number 91 fits into 771 8 times, leaving a remainder of 43.
Record the quotient 8 as the next digit in the result. 
Result so far: 4538.0
Deduct 728 from 771 and we're left with 43.
Since there are no more digits in the dividend, we add a zero to the remainder making it 430, and continue the process.

Step 7:
When dividing 430 by 91, we get 4 with a remainder of 66.
The next digit of our result is 4. 
Result so far: 4538.4
The remainder is 66 after subtracting 364 from 430.
Since there are no more digits in the dividend, we add a zero to the remainder making it 660, and continue the process.

On to step 8:
660 divided by 91 is 7 with a remainder of 23.
Record the quotient 7 as the next digit in the result. 
Result so far: 4538.47
If we take 637 away from 660, we end up with 23.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

On to step 9:
230 divided by 91 is 2 with a remainder of 48.
The number 2 becomes the next digit in our result. 
Result so far: 4538.472
The remainder is 48 after subtracting 182 from 230.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Advancing to step 10:
480 divided by 91 is 5 with a remainder of 25.
Write down 5 as next digit of the result. 
Result so far: 4538.4725
Subtract 455 from 480 to get 25.
Since there are no more digits in the dividend, we add a zero to the remainder making it 250, and continue the process.

Let's proceed to step 11:
91 can be fit into 250 2 times, resulting in a remainder of 68.
Put 2 as the next digit of the answer. 
Result so far: 4538.47252
If we subtract 182 from 250, we get 68.
Since there are no more digits in the dividend, we add a zero to the remainder making it 680, and continue the process.

Going ahead to step 12:
680 divided by 91 is 7 with a remainder of 43.
Record the quotient 7 as the next digit in the result. 
Result so far: 4538.472527
Subtract 637 from 680 to get 43.
Since there are no more digits in the dividend, we add a zero to the remainder making it 430, and continue the process.

Going ahead to step 13:
When dividing 430 by 91, we get 4 with a remainder of 66.
Write down 4 as next digit of the result. 
Result so far: 4538.4725274
If we take 364 away from 430, we end up with 66.
Since there are no more digits in the dividend, we add a zero to the remainder making it 660, and continue the process.

Moving on to step 14:
91 can be fit into 660 7 times, resulting in a remainder of 23.
Write down 7 as next digit of the result. 
Result so far: 4538.47252747
Subtract 637 from 660 to get 23.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

The quotient of the division is 4538.47252747, and the remainder is 2.3e-08.